Energy Savings Impacts of the

Advanced Energy Design Guide: Small Office Buildings

Bing Liu, P.E.

Research Engineer Pacific Northwest National Laboratory Tel: (509) 375-3710 [email protected]

Energy Use Simulation Approach

 Scoping Study:  Baseline building – Standard 90.1-1999    Advanced building – Off-the-Shelf technology Two Models: 5,000 sf and 20,000 sf office buildings Use eQuest to test run in four climate locations: Miami, Phoenix, Seattle and Duluth  Full Study:  15 representative locations in 8 DOE Climate Zones  Use DOE-2.2 directly to make 60 parametric runs for full study February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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5,000 ft² Office Prototype

     Square floor plan Single story Frame construction 20% window-to-wall ratio Single tenant February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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20,000 ft² Office Prototype

     Square floor plan 2-story Masonry construction 30% window to-wall ratio 3 tenants February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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What is in the Baseline Building?

Comply with Standard 90.1-1999

 Insulation requirements for roofs, walls, floors and slabs       U-Value and SHGC for window glazing U-Value for doors Interior lighting power density Mechanical equipment efficiency Economizer requirement And more… February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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What is in the Baseline Building?

When not specified by 90.1-1999…

    Room Thermostat:   Setpoint: 75°F cooling & 70°F heating Setback/Setup: 80°F cooling & 65°F heating Office Equipment Plug Load Schedules   Energy Policy Act Standard analysis Recent research study and peer review comments Fan Static Pressure February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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Plug Load Schedule - Weekday

20,000 sf Office Building 1.0

0.8

0.6

0.4

0.2

0.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hour of Day

Before After

ASHRAE SP102 Advanced Energy Design Guide Modeling Assumptions & Energy Usage - 20,000 sf Office Building Table 5 Baseline Modeling Assumptions (Round 2) – Seattle, WA Characteristic Architectural Features Configuration/Shape

Aspect Ratio Zoning Number of Floors Window to Wall Ratio Floor-to-Ceiling Height: Floor-to-Floor Height: Infiltration Rate Infiltration Schedule

Roof

Structure Exterior Finish Insulation Overall U-factor Emissivity Solar Reflectance

Baseline Model

1 5 zones per floor (one core + four perimeter zones) 2 30% ribbon windows uniformly distributed by orientation 9 ft 12 ft 0.038 cfm/sf of the gross exterior wall OFF_M-F_INFIL Steel deck with rigid insulation Single-ply roof membrane R-15 ci 0.063 0.87 0.23 (grey EPDM)

Data Source

SP 102 Recommendation General practice General practice ASHRAE 90.1-1989 §13.7.3.2 12 feet high Exterior Wall Off when the HVAC fan is on SP 102 Recommendation ASHRAE 90.1-1999 Table B-14 ASHRAE 90.1-1999 Table B-14 Grey single-ply membranes from

PG&E High Albedo (Cool) Roofs CASE Study Report

at http://www.newbuildings.org/downloads/co des/CoolRoof.pdf

What is in the Advanced Building?

  Envelope     Cool roofs Better insulations High performance windows and doors Overhangs for windows except facing north Interior Lighting     Reduced installed lighting power density Daylighting harvest for WWR 25% or higher Daylighting dimming control on south and north perimeter zones Occupancy Sensor February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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What is in the Advanced Building?

  Mechanical System     Higher efficiency unitary equipment in some climate zones Motorized outside air damper control Demand Control Ventilation (DCV) Lower duct friction rate: 0.08 in/100 ft vs. 0.10 in/100 ft of standard practice Service Water Heater   Higher thermal efficiency for gas-fired storage water heater or Gas-fired instantaneous water heater February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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Energy Savings of Advanced vs. Base Building (Without Plug Load)

50% 40% 30% 20%

30% Goal Over Standard 90.1-1999

10% 0% M ia m i H ou st on P ho en ix E l P aso M em S ph an is F ra nci A sco lb uq ue rq ue B al tim or e S ea ttl e B oi se C hi ca go B ur lin gt on H el en a D ul ut F h ai rb an ks 5000 sf Bldg 20,000 sf Bldg

Energy Savings of Advanced vs. Base Building (Including Plug Load)

50% 40% 30% 20% 10% 0% M ia m i Ho us to n P ho en ix E l P as o M em S ph an F is ra nc A is lb co uq ue rq ue B al tim or e S ea ttl e B oi se Ch ic ag B o ur lin gto n He le na Du lu F th ai rb an ks 5000 sf Bldg 20,000 sf Bldg

Energy Use Index

5,000 sf Office Building

120 100 80 60 40 20 0 M ia m i H ou st on Ph oe ni x El Pa so M em ph Sa is n Fra nc is co Al bu qu erq ue Ba lti m ore Se at tle Bo is e C hi ca go Bu rli ng to n H el en a D ul ut h F ai rb an ks Base Case Advanced Case

Energy Use Index

20,000 sf Office Building

80 60 40 20 0 M ia m i H ou st on Ph oe ni x El Pa so M em ph is n Fra nc is Al co bu qu erq ue Ba lti m ore Sa Se at tle Bo is e C hi ca go Bu rli ng to n H el en a D ul ut F h ai rb an ks Base Case Advanced Case

60% 50%

Comparison of Energy Savings

5,000 sf Office Building Average Savings of All the Climate Zones = 38% 49.1%

40%

35.6% 36.4%

30% 20% 10% 0%

Miami

Lighting

Baltimore

Cooling Heating Fans

Duluth

SWH

50% 40%

Comparison of Energy Savings

20,000 sf Office Building Average Savings of All the Climate Zones = 38% 38% 43% 35%

30% 20% 10% 0%

Miami

Lighting Cooling

Baltimore

Heating Fans

Duluth

SWH

Advanced Simulation Challenges

 Real windows vs. DOE-2 window library  Window Shading Coefficient Method   Window Library Method Window Layers Method February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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Advanced Simulation Challenges

 Occupancy sensor  DOE-2 doesn’t have occupancy sensor module  Modify the lighting schedule to estimate the potential energy savings from the occupancy sensors February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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Lighting & Occupancy Sensor Schedule 1.10

1.00

0.90

0.80

0.70

0.60

0.50

0.40

0.30

0.20

0.10

0.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Weekday - Hour of Day

Lighting Lighting with Occupancy Sensor

Advanced Simulation Challenges

 Demand ventilation control  No CO2 sensor module in DOE-2  Modify the outside air change rate to reflect the average reduction of the outside intake using CO2 sensor – 20% February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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Advanced Simulation Challenges

 Motorized outside air damper control  Potentially saving cooling and heating energy during nights by closing the OA damper when fans cycle on to maintain space setback temperature  Hourly-based simulation may over estimate the energy savings from the motorized outside air damper in the cold climates February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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Questions?

Bing Liu, P.E.

Pacific Northwest National Laboratory Tel: (509) 375-3710 [email protected]

February 7, 2005 ASHRAE Winter Meeting, Orlando, Fla.

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